There is substantial literature describing the use of urea-formaldehyde liquid resins for application to textiles and similar cellulosic and synthetic resin substrates. A number of resins of this type are described in my prior U.S. Pat. Nos. 3,883,462; 3,983,269; 3,984,367; 3,990,977; 4,119,598; and 4,215,172. My prior U.S. Pat. Nos. 4,419,401, dated Dec. 16, 1983 and 4,427,745, dated Jan. 24, 1984, also disclose resinous systems which have excellent fire retardant characteristics.
A number of attempts have been made to condense such systems into powders for use in various materials which present fire hazard problems, and which must be compatible with melamine and urea-formaldehyde adhesives as well as adhesives of various types for use in making plywood and particle board.
The powdered compositions of the present invention are improvements over the aqueous compositions of my prior patents and applications in providing a very stable product which is more efficient than a liquid, reduces shipping costs, and is more fire retardant per pound.